Sensation and Perception

Question 1

Perceptual organization

Answer 1

The ability to use bottom up and top down processing to create a complete picture or idea.

Question 2

What are the Gestalt Principles?

Answer 2

Law of proximity Law of similarity Law of good continuation Subjective countours Law of closure

Question 3

Law of proximity

Answer 3

Elements close to one another tend to be perceived as a unit.

Question 4

Law of similarity

Answer 4

Objects that are similar tend to be grouped together

Question 5

Law of good continuation

Answer 5

Elements that appear to follow in the same pathway tend to be grouped together. That is, there is a tendency to perceive continous patterns in stimuli rather than abrupt changes

Question 6

Subjective contours

Answer 6

Have to do with perceiving contours and therefore shapes that are not actually present in the stimulus

Question 7

Law of closure

Answer 7

When a space is enclosed by a countour it tends to be perceived as a complete figure

Question 8

Bottom up processing

Answer 8

Data driven

Refers to object recognition by parallel processing and feature detection. Essentially, the brain takes the individual sensory stimuli and combines them together to create a cohesive image before determing what the objet is.

Question 9

Top down processing

Answer 9

Conceptually driven

Driven by memories and expectations that allow the brain to recognize the whole object and then recognize the components based on these expectations. Top down processing allows us to quickly recognize objects without needing to analyze specific parts

Question 10

What is sensation?

Answer 10

Similar to transduction. Performed by receptors in the peripheral nervous system. Thought of as a raw signal, which is unfiltered and unprocessed until in enters the CNS

Question 11

What is perception?

Answer 11

Refers to the processing of sensory information to make sense of insignificance. Perception helps us make sense of the world

Question 12

Distal stimuli

Answer 12

A stimulus that originates outside of the body. part of the outside world. For example a campfire

Question 13

Proximal stimuli

Answer 13

The photons that reach the observers rods and cones, as well as the heat the Observer feels.

Proximal stimuli directly interact with and affect the sensory receptors, And inform the Observer about the presence of the distal stimuli

Question 14

Absolute threshold

Answer 14

The minimum of stimulus energy that is needed to activated sensory system

Question 15

Psychophysical discrimination testing

Answer 15

The participant is presented with a stimulus that is very slightly and then his asked to identify whether there is a difference in the second stimulus. The difference between the current stimulus and the original is increased until the participant reports noticing a change.

Question 16

Weber’s Law

Answer 16

States that there is a constant ratio between the changing stimulus magnitude needed to produce a just noticable difference and the magnitude of the original stimulus

Question 17

Signal detection theory

Answer 17

Focuses on the changing our perception of the same stimuli depending on both internal and external context

the detection of a stimulus depends on both the intensity of the stimulus and the physical/psychological state of the individual

Question 18

Possible outcomes for signal detection experiment trial

Answer 18

Question 19

Motion parallax

Answer 19

Objects that are close seem to move past us faster when we go past them. These closer objects also seem to be moving backwards. Objects that are farther away seem to go a lot slower as we go past them. they also seem to be moving forward with us.

Question 20

Convergence

Answer 20

Objects that are closer make you turn your eyes inward more

Question 21

Parallel processing

Answer 21

The ability to simultaneously analyze and combine information regarding color, shpae and motion

Question 22

What do cones detect? What are the 3 types of cones? What wavelengths to they absorb?

Answer 22

Cones are used for color vision and to sense fine details.

Most effective in bright light and come in 3 forms

1. Short (S) Also called blue
2. Medium (M) Also called green
3. Long (L) Also called red

Question 23

What do rods detect?

Answer 23

Rods only allow sensation of light and dark because they all contain a single pigment called rhodopsin. Low sensitivity. Permit night vision

Question 24

Describe the Visual pathway

Answer 24

Corniea –> pupil –> Lens –> Vitreous –> retina (rods and cones –> bipolar cells –> ganglion cells) –> optic nerve –> optic chiasm –> optic tract –> lateral geniculate nucleus (LGN) of thalamus –> radiations through parietal and temporal lobes –> Visual cortex in occipital lobe

Question 25

Function of cornea

Answer 25

Gathers and focuses incoming light

Question 26

Function of pupil

Answer 26

Allows passage of light from the anterior to posterior chamber

Question 27

Function of Iris

Answer 27

Controls the size of the pupil

Question 28

Function of ciliary body

Answer 28

Provides aqueous humor; accomodation of the lens

Question 29

Funciton of canal of schlemm

Answer 29

Drains aqueous humor

Question 30

Function of Lens

Answer 30

Refracts incoming light to focus it on the retina

Question 31

Function of sclera

Answer 31

Provides structural support

Question 32

What is the somatosensory homunculus?

Answer 32

A map of the body in your brain

Question 33

Labelled lines model

Answer 33

abeled-line model predicts that individual taste receptor cells will respond to only a single taste quality. Information about each taste quality is then transmitted by separate afferent pathways to the gustatory cortex via the medulla and the thalamus

Question 34

Which tastes are G coupled?

Answer 34

Sweet umami bitter

Question 35

Which tastses require ion channels?

Answer 35

Sour Salty